1. Field of Invention
This machine relates to a medical apparatus, specifically to an improved medical apparatus to immobilize a vascular structure so that it may be punctured with a needle.
2. Description of Prior Art
The piercing of body conduits, namely arteries and veins, is necessary at times for obtaining specimens for analysis, administration of fluids and medications, transfusion of blood, etc. It takes a considerable amount of skill to be able to locate the conduit, immobilize it, and then insert the needle so as to minimize pain to the patient.
There are multiple problems inherent in this procedure. These conduits, especially veins, are difficult to hold steady. They tend to "roll" (move laterally) when the needle is being inserted. If the needle does get inserted into the vein, the vein may collapse. If the needle is inserted and then advanced, the needle may go through the vein wall because of the serpentine nature of this type of blood vessel. Then the blood in the vein, or the intravenous fluid being introduced, extravasates into the surrounding tissues, causing swelling, bruising, and pain.
When these events occur, it is necessary to start again. Because of these multiple punctures,
1) the patient experiences more discomfort and anxiety, PA0 2) there is an increased chance for infection, PA0 3) there are a decreased number of sites for immediate intravenous access, PA0 4) the operator requires additional time, and PA0 5) there are added expenses because of the extra supplies needed. PA0 1) it is flat and rigid and does not conform to the surface of the body where the vein to be punctured lies, PA0 2) it has one sized notch so it cannot be adjusted for the caliber of the vein, PA0 3) it is unwieldy to use, and PA0 4) it is only good for very superficial veins with minimal subcutaneous tissue. Here it is easy to get around the vein and immobilize it bilaterally (although it may still move when a needle tries to puncture it). But deeper blood vessels have more intervening skin and subcutaneous structures so the pressure is more superior than bilateral and the vein can still move laterally and "roll". Also this pressure can flatten the vein, making it harder to puncture. This is a major limitation of a rigid notched device and I'll refer to it as such in several of the following patents. PA0 1) it is flat and rigid and does not conform to the surface of the body where the vein lies, PA0 2) it would be too expensive to manufacture to be disposable, so it would have to be sterilized before each use, PA0 3) it uses tourniquets to position the vein retainer over the vein; this greatly limits the location of the veins that may be used since the vein has to be in such a location where the whole device can be placed on the extremity, PA0 4) it is complicated to manufacture, and PA0 5) it is relatively complicated to use. PA0 1) it takes coordination to operate the spring mechanism of the metal plate and keep it under constant tension so that the sides of the notch are up against the sides of the vein, without collapsing the vein, PA0 2) it can induce operator fatigue, and PA0 3) it will not immobilize smaller caliber veins very well. PA0 1) it would be too expensive to manufacture to be disposable, so it would need to be sterilized before each use, PA0 2) the vein immobilizer is connected to a tourniquet thereby limiting the areas on the body where a vein could be used to those where the tourniquet could be applied in close proximity to the vein, PA0 3) there is a fixed distance between the two downsloping legs so it cannot be adjusted for the caliber of the vein, PA0 4) it has the limitations of a rigid notched device as detailed under the above Silliman reference, PA0 5) it is complicated to manufacture, and PA0 6) it is complicated to use. PA0 1) it has one sized notch so it cannot be adjusted for the caliber of the vein, PA0 2) it has to be used with a syringe, which limits its usefulness (i.e., it cannot be used with those needles used to start intravenous lines), PA0 3) it would be too expensive to manufacture to be disposable so it would need to be sterilized before each use, and PA0 4) it has the limitations of being a rigid notched device as initially detailed under the above Silliman reference. PA0 1) there is a fixed distance between the two descending legs of the device so it cannot be adjusted for the caliber of the blood vessel, PA0 2) it has the limitations of being a rigid notched device as mentioned in the above Silliman reference, and PA0 3) it is rigid and does not conform to the area of the body where the blood vessel is. PA0 1) it does not conform very well to different surfaces of the body where the vein may lie, PA0 2) it is associated with a tourniquet, which limits the area of the body where a vein could be used to those areas where the tourniquet could be applied in close proximity to the vein, PA0 3) it is hard to use with small caliber veins, and PA0 4) it would not be useful to immobilize deeper veins. PA0 1) it is rigid and fiat--not conforming to the body surface where the vein is located, PA0 2) the groove and slot are too long to straighten and immobilize serpentine veins, PA0 3) its design limits it to those areas of the body where the straps can be placed on an extremity, PA0 4) it has only one sized groove so it cannot be adjusted for the caliber of the vein, PA0 5) it has the limitations of being a notched device as initially mentioned under the above Silliman reference, PA0 6) it is complicated to manufacture, and PA0 7) it is difficult to use. PA0 1) it is too long to straighten and immobilize serpentine veins, PA0 2) as it is designed, the needle actually punctures the unstabilized part of the vein, away from the parallel members, PA0 3) it is made of only one sized parallel members so it cannot be adjusted for the caliber of the vein, PA0 4) it does not conform to the body surfaces where the vein lies, and PA0 5) it has the limitation of being a rigid notched device as initially discussed under the above Silliman reference. PA0 1) it is flat and rigid limiting its use on different surfaces of the body, PA0 2) it has one sized groove so it cannot be adjusted to the caliber of the vein, PA0 3) the groove and notch are too long to straighten and immobilize serpentine veins, and PA0 4) it has the limitations of being a notched device as initially mentioned under the above Silliman reference. PA0 1) it will not immobilize smaller caliber veins very well, PA0 2) it requires coordination to apply constant tension to the divergent panels without collapsing the vein, and PA0 3) it can induce operator fatigue. PA0 (a) is flexible so it can contour to different body surfaces--hands, feet, arms, legs, scalp, neck, etc.; PA0 (b) is made of a clear flexible material so veins can be seen in the device; PA0 (c) is made of one simple piece; PA0 (d) is easy to manufacture; PA0 (e) is easy to use; PA0 (f) is easy to hold the vein to be punctured in place after it is stabilized by the immobilizer--a person can use one to two fingers of one hand to exert mild pressure on the immobilizer; PA0 (g) has various sized grooves to accommodate a wide variety of different sized blood vessels; PA0 (h) can immobilize veins at different depths under the surface of the skin; PA0 (i) immobilizes a vein on three sides--bilaterally and superiorly; PA0 (j) is disposable so it will not need resterilization; PA0 (k) is independent of the positioning of a tourniquet so it has greater flexibility in choosing a vein to immobilize; PA0 (l) has grooves short enough to be able to straighten out superficial serpentine veins; PA0 (m) can be used to immobilize small caliber veins; PA0 (n) immobilizes a vein so that it may be punctured with a syringe or other needle devices; PA0 (o) is inexpensive to manufacture; PA0 (p) increases the speed of obtaining a venipuncture; PA0 (q) decreases the discomfort of obtaining a venipuncture since fewer tries would be needed; and PA0 (r) decreases the cost since there would be fewer sticks and fewer supplies needed.
The operator may try to immobilize the vein with his or her fingers. This however is fraught with the danger of the operator puncturing one of his or her fingers with the needle and being subject to all the attendant risks of getting blood borne diseases such as hepatitis B and HIV infections as well as bacterial infections at the puncture site.
Multiple devices have been invented to immobilize vascular structures in the past. None are now in widespread clinical use, as all have major problems that limit their usefulness as detailed below.
One of the first vascular stabilizing devices is shown in U.S. Pat. No. 1,561,116 (Silliman) which discloses a hand held vein stabilizer having a fiat plate with a notch. The plate is placed on the skin, with the notch placed over a vein and directed proximally toward the heart.
The difficulties with this device are that
U.S. Pat. No. 1,824,516 (Tyvand) discloses a vein retainer including a complex flat metal structure that is placed over a vein and held there by tourniquets. It has two opposing sliding metal plates with facing downcurving edges that can be made to move toward each other, with the downcurving edges immobilizing the vein.
The difficulties with this device are that
U.S. Pat. No. 2,103,174 (Posada) discloses a `V` shaped metal device that is located at one end of a tourniquet. This metal device has a notch in the center of the `V` to immobilize the vein to be punctured. By pushing in the center of the device to flatten the `V`, the notch in the center can get smaller and accommodate different sized veins.
The difficulties with this device are that
U.S. Pat. No. 2,234,961 (Canada) discloses a complex mechanism consisting of a tourniquet on top of which is attached a pivoted metal device. This device has two downsloping legs that can be positioned to press on either side of the vein to be punctured.
The difficulties with this device are that
U.S. Pat. No. 3,324,854 (Weese) discloses a device to be attached to the barrel of a syringe to immobilize a vein. This device has a notch in it to immobilize the vein to be punctured.
The difficulties with this device are that
U.S. Pat. No. 4,196,735 (Ayer) discloses a fiat device with two descending legs to hold down an artery by pressing down on both sides of the artery.
The difficulties of this device are that
U.S. Pat. No. 4,314,568 (Loving) discloses a fiat plate with a slot in the center, the two halves of which can move together to accommodate different sized veins. The device is attached to a tourniquet to dilate the vein to be punctured.
The difficulties with this device are that
U.S. Pat. No. 4,316,461 (Marais et al.) discloses a fiat, rigid base plate with a major longitudinal notch and groove to embrace a vein. Once the intravenous needle is introduced, the whole assembly is held in place with a pair of straps after the intravenous tubing is attached to the plate.
The difficulties with this device are that
U.S. Pat. No. 4,332,248 (DeVitis) discloses a device comprised of a long parallel pair of members. These members prevent the lateral movement of a vein while the vein is being pierced with a needle.
The difficulties with this device are that
U.S. Pat. No. 4,586,924 (Lanning) discloses a fiat plate with a notch at one end. This notch leads to a groove under the plate. This combination immobilizes a vein.
The difficulties with this device are that
U.S. Pat. No. 5,254,095 (Harvey) discloses a stabilizer for blood vessels that looks like a shortened, widened forceps and functions similarly.
The difficulties with this device are that
Thus there is a great need for a vascular stabilizer that overcomes all the disadvantages listed in the above prior patents and this will be described below.